The angst when the Tigers unexpectedly traded Doug Fister to the Washington Nationals was understandable.

Fister, during his 2 1-2 seasons with the Tigers, was everything this town appreciates from its favorite ball players.

Fister doesn’t have the best fastball. At 88.8 mph it was the fifth-slowest among MLB regular starting pitchers in 2013. Yet, he developed a swing-back action to it, learned to pitch effectively inside to hitters from both sides of the plate and refined his curveball into a killer pitch.

Fister didn’t only survive, he thrived – a 32-20 record, a 3.29 ERA and a WHIP below 1.2 as a Tiger.

You can debate whether the Tigers received enough in return for Fister (left-handed reliever Ian Krol, utility infielder Steve Lombardozzi and pitching prospect Robbie Ray), but it could be a moot factor regardless - if Rick Porcello blossoms.

While it is left-hander Drew Smyly who is moving into the rotation to replace Fister, it is Porcello who is moving up in the rotation. Fister often gave the Tigers’ top-of-the-rotation performance from the backend.

It’s been a major edge the Tigers have held over other MLB clubs.

One thing you never hear about Fister is, “He should be so much better.”

You hear it all the time about Porcello.

It is time for Porcello to transform from an inconsistent young pitcher experiencing growing pains into a top-line starter.

Porcello has carried the label as an enigma. It’s unfair. Porcello is just 25 years old. Yet, this will be his sixth MLB season.

And each prior season has presented a similar scenario. Porcello has had some excellent moments while posting a 61-50 record, but the lows have been frustrating. He has a 4.51 career ERA – which is too high given what he brings to the mound in regard to pitch menu. So is his career WHIP, which is above 1.3.

It should be noted Fister was older by several month than Porcello is now when he made his MLB debut. Fister, 30, actually has less MLB service time, thrown fewer innings and made 19 fewer starts than Porcello.

The big difference has been ERA. Fister’s career ERA is nearly a run lower than that of Porcello – 3.53 compared to 4.51.

The scouting contrast between Porcello and Fister clearly goes to Porcello, though.

Although Porcello’s best pitch, a two-seam (sinking) fastball isn’t meant to light up the radar gun, he still throws it harder than Fister. He also has a four-seam (straight and hard) fastball with high velocity, often registering at 94 mph or better.

Added in with an improved curveball, which made Porcello more effective against left-handed hitters the second half in ’13, gives a clear edge to Porcello.

In fairness to Fister, his mph is misleading. He throws mostly two-seam fastballs, and at 6-8, there is much tilt on fastball, and the steep angle adds to its effectiveness. And there is, of course, the above-mentioned movement.

However, Porcello is 6-5. The downward plane added with the usual hard sink on his two-seam fastball should be incredibly effective.

Why hasn’t he always been?

It’s been mostly because when Porcello doesn’t have his two-seam fastball working, he’s had difficulty finding a Plan B and adjusting on the fly.

Ideally, Porcello set ups hitters with his two-seam fastball down in the zone, then changes the eye level with his four-seam fastball up - and then mixes in his improved curveball for three very good pitches.

Fister has been much better at adjusting when struggling. When he pitched for Seattle, he didn’t have the swing-back fastball. His curveball went from mediocre to off the charts. He keeps finding a way.

There is, however, reason to believe there is similar hope Porcello will “find” himself this season.

Porcello won 9 of his last 11 decisions in ‘13, his ERA dropping from 5.21 at the end June to 3.47 for his remaining 16 appearances.

Having slick-fielding shortstop Jose Iglesias and solid second baseman Ian Kinsler behind him should benefit Porcello, a ground ball pitcher.

After trading Fister, the Tigers need a so-called breakout season from Porcello for their master plan to work.